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Characterization And Modeling Of Discontinuous Fiber Composites, Kenneth M. Serrano Rodriguez, Imad Hanhan, Ronald F. Agyei, Michael Sangid 2018 University of Puerto Rico, Mayaguez

Characterization And Modeling Of Discontinuous Fiber Composites, Kenneth M. Serrano Rodriguez, Imad Hanhan, Ronald F. Agyei, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

Composite materials, which are light and strong, are of great interest to engineers in the aerospace industry. Specifically in this work, a discontinuous short fiber reinforced polymer composite whose matrix is Polypropylene and fibers are Electric-glass oriented in different directions was studied. The performance of this material is highly dependent on its microstructure, and therefore the objective of this research is to non-destructively characterize the microstructure of the composite material. This includes characterization of its fiber orientation and length, fiber volume fraction, and void volume fraction. To do this, X-ray micro-computed tomography has been used, providing two dimensional cross-sectional images ...


Design Of Selectively Compliant Morphing Wind Turbine Blade Section Using Bistable Laminate For Passive Load Alleviation, Abhishek Chopra, Dr. Andres Arrieta, Janav Udani, Jose Rivas Padilla 2018 Rutgers University - New Brunswick/Piscataway

Design Of Selectively Compliant Morphing Wind Turbine Blade Section Using Bistable Laminate For Passive Load Alleviation, Abhishek Chopra, Dr. Andres Arrieta, Janav Udani, Jose Rivas Padilla

The Summer Undergraduate Research Fellowship (SURF) Symposium

The design of passively controlled compliant morphing structures for large scale wind turbine blades has been of interest due to the inherent advantages of lower mass and reduced complexity over their active counterparts. Previous studies have indicated that embedding a locally bi-stable element within the turbine blade section successfully allows for achieving passive load alleviation. The embedded bi-stable member switches from one stable state to another at a critical aerodynamic load. This local structural change results in a global shift in the aeroelastic response of the blade section. Building on these preliminary results, this research investigates a two- dimensional wind ...


Design Survey Of Laminated Composite I-Beam, Mrinmoy Saha 2018 Utah State University

Design Survey Of Laminated Composite I-Beam, Mrinmoy Saha

All Graduate Plan B and other Reports

Composite I-beams are popular for high-strength low-weight applications. Learning the macro-mechanics and designing the composite I-beam properly are necessary. In this report, a design overview of the composite I-beam is discussed which is based on classical lamination theory where it includes the homogenization approach, the plane stress assumption and the Kirchhoff hypothesis. Using these assumptions, a method was developed to come up with the effective material properties of a beam. Formulas to calculate maximum deflection and maximum bending stress and shear stress and the stress concentration at the connection of web-flange are discussed which describe ways for designing and manufacturing ...


Modification Of A Ground Based Atomic Oxygen Simulation Apparatus To Accommodate Three Dimensional Specimens, Charles Ward, Charles Ward, Charles Ward 2018 California Polytechnic State University, San Luis Obispo

Modification Of A Ground Based Atomic Oxygen Simulation Apparatus To Accommodate Three Dimensional Specimens, Charles Ward, Charles Ward, Charles Ward

Master's Theses and Project Reports

The space environment presents various challenges when designing systems and selecting materials for applications beyond Earth’s atmosphere. For mission success, these challenges must be considered. One of the detrimental aspects of the space en- vironment is Atomic Oxygen, AO. Only present in harmful quantities in Lower Earth Orbit, LEO, AO causes significant damage to materials by breaking molecular bonds. California Polytechnic State University’s, Cal Poly’s, space environments laboratory features an apparatus capable of simulating this environment. Very thin or short samples were tested to observe the mass loss due to erosion of the sample material. Recent modifications ...


Thermally Stable Super-Hydrophobic Surface Creation, Caleb Turner 2018 Portland State University

Thermally Stable Super-Hydrophobic Surface Creation, Caleb Turner

Undergraduate Research & Mentoring Program

Thermally stable super-hydrophobic surface coatings are critical to applications in low gravity fluid dynamics, and in particular Leidenfrost effects. The challenges of manufacturing different super-hydrophobic coatings that are thermally stable, semi-transparent, and environmentally safe at desired operating temperatures is pursued in order to explore the applications of such coatings aboard spacecraft. A catalog of surface coating manufacturing procedures is tabulated with measures for static contact angle, thermal stability, and transparency. These quantities and methods serve as a foundation for both technology applications and follow on experimentation concerning low gravity fluid mechanics at the Portland State Dryden Drop Tower lab.


A Novel Magnetorheological Fluid Damper For A Small Spacecraft With Flexible Appendages, Robert Waelchli 2018 Embry-Riddle Aeronautical University

A Novel Magnetorheological Fluid Damper For A Small Spacecraft With Flexible Appendages, Robert Waelchli

Dissertations and Theses

Small satellites have become increasingly popular over the past thirty years, particularly since the adoption of the common CubeSat architecture early this century. Because of their restricted volume and electrical budgets however, there are practical limits to the missions that small satellites may adopt. One potential near-term solution to the problem of limited electrical power may be the adoption of larger, flexible solar arrays. However, spacecraft with flexible appendages have historically presented attitude control challenges relating to platform stability given the dynamic response of the flexible components to applied torques. These challenges may be particularly disruptive to a small spacecraft ...


Phase Field Study Of Surface-Induced Melting And Solidification From A Nanovoid: Effect Of Dimensionless Width Of Void Surface And Void Size, Anup Basak, Valery I. Levitas 2018 Iowa State University

Phase Field Study Of Surface-Induced Melting And Solidification From A Nanovoid: Effect Of Dimensionless Width Of Void Surface And Void Size, Anup Basak, Valery I. Levitas

Physics and Astronomy Publications

The size effect and the effects of a finite-width surface on barrierless transformations between the solid (S), surface melt (SM), and melt (M) from a spherical nanovoid are studied using a phase field approach. Melting (SM → M and S → M) from the nanovoid occurs at temperatures which are significantly greater than the solid-melt equilibrium temperature θe but well below the critical temperature for solid instability. The relationships between the SM and M temperatures and the ratio of the void surface width and width of the solid-melt interface, Δ⎯⎯⎯, are found for the nanovoids of different sizes. Below a critical ratio ...


Numerical Simulation Of A High Strain Rate Biaxial Compression Apparatus, Michael Lagieski 2018 Washington University in St. Louis

Numerical Simulation Of A High Strain Rate Biaxial Compression Apparatus, Michael Lagieski

Engineering and Applied Science Theses & Dissertations

Few experimental methods today are capable of exploring the strength of materials at high strain rates (105 s-1). Those that are capable, such as the Split Hopkinson Bar, Taylor Anvil and Plate Impact suffer from instability and are generally limited to one dimensional wave propagation. Of particular interest is material response under biaxial compression, similar to that seen in inertial confinement fusion. Laser fusion fuel pellets typically undergo large strain rates as well as plastic deformation and non-linear behavior. This work briefly outlines an experimental procedure designed to replicate these large strain rates under biaxial compression using spherical ...


Durability Assessment Of Soft Elastomeric Capacitor Skin For Shm Of Wind Turbine Blades, Austin Downey, Anna Laura Pisello, Elena Fortunati, Claudia Fabiani, Francesca Luzi, Luigi Torre, Filippo Ubertini, Simon Laflamme 2018 Iowa State University

Durability Assessment Of Soft Elastomeric Capacitor Skin For Shm Of Wind Turbine Blades, Austin Downey, Anna Laura Pisello, Elena Fortunati, Claudia Fabiani, Francesca Luzi, Luigi Torre, Filippo Ubertini, Simon Laflamme

Civil, Construction and Environmental Engineering Conference Presentations and Proceedings

Renewable energy production has become a key research driver during the last decade. Wind energy represents a ready technology for large-scale implementation in locations all around the world. While important research is conducted to optimize wind energy production efficiency, a critical issue consists of monitoring the structural integrity and functionality of these large structures during their operational life cycle. This paper investigates the durability of a soft elastomeric capacitor strain sensing membrane, designed for structural health monitoring of wind turbines, when exposed to aggressive environmental conditions. The sensor is a capacitor made of three thin layers of an SEBS polymer ...


Manufacturing Process Simulation – On Its Way To Industrial Application, Dennis Otten, Tobias A. Weber, Jan-Christoph Arent 2018 University of Applied Sciences Augsburg

Manufacturing Process Simulation – On Its Way To Industrial Application, Dennis Otten, Tobias A. Weber, Jan-Christoph Arent

International Journal of Aviation, Aeronautics, and Aerospace

Manufacturing process simulation (MPS) has become more and more important for aviation and the automobile industry. A highly competitive market requires the use of high performance metals and composite materials in combination with reduced manufacturing cost and time as well as a minimization of the time to market for a new product. However, the use of such materials is expensive and requires sophisticated manufacturing processes. An experience based process and tooling design followed by a lengthy trial-and-error optimization is just not contemporary anymore. Instead, a tooling design process aided by simulation is used more often. This paper provides an overview ...


Nanoindentation Study Of Corrosion-Induced Grain Boundary Degradation In A Pipeline Steel, Denizhan Yavas, Pratyush Mishra, Abdullah Alshehri, Pranav Shrotriya, Kurt R. Hebert, Ashraf F. Bastawros 2018 Iowa State University

Nanoindentation Study Of Corrosion-Induced Grain Boundary Degradation In A Pipeline Steel, Denizhan Yavas, Pratyush Mishra, Abdullah Alshehri, Pranav Shrotriya, Kurt R. Hebert, Ashraf F. Bastawros

Aerospace Engineering Publications

High-strength low-alloy steels used for oil and gas pipelines are vulnerable to intergranular stress corrosion cracking in moderately alkaline soils. The mechanism of corrosion-induced embrittlement under such conditions is not yet understood. Nanoindentation was used to detect localized degradation of mechanical properties near internal grain boundaries of X-70 steel undergoing intergranular corrosion at active dissolution potentials at pH 8.2. The measurements identified a one-micron thick mechanically-degraded layer with 25% reduced hardness near corroded grain boundaries. It is suggested that the corrosion process may introduce an active softening agent, possibly non-equilibrium lattice vacancies generated by oxidation.


Model-Assisted Approach For Probability Of Detection (Pod) In High-Temperature Ultrasonic Nde Using Low-Temperature Signals, Prathamesh N. Bilgunde, Leonard J. Bond 2018 Iowa State University

Model-Assisted Approach For Probability Of Detection (Pod) In High-Temperature Ultrasonic Nde Using Low-Temperature Signals, Prathamesh N. Bilgunde, Leonard J. Bond

Aerospace Engineering Publications

Advanced piezoelectric-based ultrasonic transducers offer the potential for in-coolant nondestructive testing (NDT) measurements at high temperatures (HTs), including during hot standby (~260°C) for liquid-sodium–cooled advanced small modular reactors. The reliability of the NDT measurements is typically quantified by the probability of detection (POD) measured at the corresponding temperature. Obtaining such data in liquid sodium is challenging. Using a model-assisted POD approach, a transfer function is reported that enables data obtained on low carbon steel specimens at room temperature to give an estimated POD at an HT. A primary source of the difference in POD between room temperature and ...


Assessment And Comparison Of Aviation Manufacturing Industries Throughout Mexico And Brazil, Omar E. Morsi, Kelly A. Whealan-George, Aaron D. Clevenger 2018 Embry-Riddle Aeronautical University

Assessment And Comparison Of Aviation Manufacturing Industries Throughout Mexico And Brazil, Omar E. Morsi, Kelly A. Whealan-George, Aaron D. Clevenger

International Journal of Aviation, Aeronautics, and Aerospace

This literature review serves to provide insight and understanding in regards to the evolving aviation manufacturing industry throughout the globe and more specifically, Mexico and Brazil. Increased demand for aircraft units both in the commercial and private sectors have led to unprecedented expansions in aircraft manufacturing across the industry. In order to illuminate certain potentials and current growth levels of such industries, this review will delve into an array of information and specifications in regards to economic, political, and cultural influences throughout both Mexican and Brazilian markets respectively. In conclusion, the review will identify the transformation of an aviation manufacturing ...


High Strain Rate Dynamic Response Of Aluminum 6061 Micro Particles At Elevated Temperatures And Varying Oxide Thicknesses Of Substrate Surface, Carmine Taglienti 2018 University of Massachusetts Amherst

High Strain Rate Dynamic Response Of Aluminum 6061 Micro Particles At Elevated Temperatures And Varying Oxide Thicknesses Of Substrate Surface, Carmine Taglienti

Masters Theses

Cold spray is a unique additive manufacturing process, where a large number of ductile metal micro particles are deposited to create new surface coatings or free-standing structures. Metallic particles are accelerated through a gas stream, reaching velocities of over 1 km/s. Accelerated particles experience a high-strain-rate microscopic ballistic collisions against a target substrate. Large amounts of kinetic energy results in extreme plastic deformation of the particles and substrate. Though the cold spray process has been in use for decades, the extreme material science behind the deformation of particles has not been well understood due to experimental difficulties arising from ...


Thermo-Mechanical Coupling For Ablation, Rui Fu 2018 University of Kentucky

Thermo-Mechanical Coupling For Ablation, Rui Fu

Theses and Dissertations--Mechanical Engineering

In order to investigate the thermal stress and expansion as well as the associated strain effect on material properties caused by high temperature and large temperature gradient, a two-way thermo-mechanical coupling solver is developed. This solver integrates a new structural response module to the Kentucky Aerothermodynamics and Thermal response System (KATS) framework. The structural solver uses a finite volume approach to solve either hyperbolic equations for transient solid mechanics, or elliptic equations for static solid mechanics. Then, based on the same framework, a quasi-static approach is used to couple the structural response and thermal response to estimate the thermal expansion ...


Articulating Axial-Flow Turbomachinery Rotor Blade For Enabling Variable Speed Gas Turbine Engine, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo, Fei Xu, Ming-Chen Hsu, Yuri Bazilevs 2018 United States Army Research Laboratory

Articulating Axial-Flow Turbomachinery Rotor Blade For Enabling Variable Speed Gas Turbine Engine, Muthuvel Murugan, Anindya Ghoshal, Luis Bravo, Fei Xu, Ming-Chen Hsu, Yuri Bazilevs

Mechanical Engineering Conference Presentations, Papers, and Proceedings

Current technology gas turbine engines are generally optimized to operate at nearly a fixed speed with fixed blade geometries for the design operating condition. When the operating condition of the engine changes, the flow incidence angles may not be optimum with the blade geometries resulting in reduced off-design performance. But, if we have the capability of articulating the pitch angle of axial-flow compressor/turbine blades in coordination with adjustable stator vanes, it can improve performance by maintaining flow incidence angles within the optimum range for given blade geometries at all operating conditions. Maintaining flow incidence angles within the optimum range ...


Design Of Shape-Conforming Nosecone For Optimal Fluid Flow From Transonic To Supersonic Range, Anna Tombazzi 2018 The University of Akron

Design Of Shape-Conforming Nosecone For Optimal Fluid Flow From Transonic To Supersonic Range, Anna Tombazzi

Honors Research Projects

Modern flight vehicles, such as rockets, missiles, and airplanes, experience a force caused by forebody wave drag during the flight. This drag force is induced when the frontal point of each vehicle breaks the pressure wave during flight. Efforts to reduce this wave drag force to improve flight efficiency include modifying the nosecone profile of the flight vehicles to lower the drag force.

This project revolved around creating a design to make the transformation of nosecone shapes from a ¾ Parabolic profile to a ½ Power Series profile possible, mid-flight. Using a novel nosecone assembly, shape memory alloys (SMAs) and ...


Guardian Condor, Kevin Bayonnet 2018 The University of Akron

Guardian Condor, Kevin Bayonnet

Honors Research Projects

Our group has teamed up with Dr. Williams from Discovery Lab Global to research the capabilities of 3D printed Unmanned Aerial Vehicles (UAVs). The goal of our project is to deliver a 3D printed glider prototype which can later be fitted with electronics for controlled flight. The glider must also carry a payload of 2 to 3 pounds in addition to the electronics. These requirements must be met all while using a basic 3D printer with low cost plastic

Throughout the Fall 2017 semester, our group made a significant amount of progress by completing the conceptual design portion of the ...


Investigation Of 2195 And 2219 Post Weld Heat Treatments For Additive Friction Stir Lap Welds, Matthew Champagne 2017 University of New Orleans

Investigation Of 2195 And 2219 Post Weld Heat Treatments For Additive Friction Stir Lap Welds, Matthew Champagne

University of New Orleans Theses and Dissertations

To evaluate potential uses for friction stir welding in additive manufacturing, two separate parts were fabricated, one of 2195-T84 and the other 2219-T87, utilizing fixed pin techniques and additive lap welds. The parts were cut into samples, artificially aged and subjected to Rockwell hardness (HRB), Vickers hardness, micrographic photography, and metallographic imaging on both pre- and post- heat treatment. Additionally, tensile testing was performed on the heat-treated samples. A comparisons of test results showed a minimal increase in the yield strength of the 2195-T84 samples compared to as-welded tensile results obtained from a previous project. The ultimate tensile strength was ...


Scaled Experiment Investigating Sonomechanically Enhanced Inert Gas Sparging Mass Transfer, Floren Rubio, Leonard J. Bond, Edward Blandford 2017 University of New Mexico

Scaled Experiment Investigating Sonomechanically Enhanced Inert Gas Sparging Mass Transfer, Floren Rubio, Leonard J. Bond, Edward Blandford

Aerospace Engineering Publications

One of the leading advanced reactor concepts is the fluoride salt high temperature reactor (FHR) currently under investigation. This design utilizes a fluoride molten salt, flibe (2 LiF/BeF2), as the primary coolant. One challenge of employing flibe as a coolant is the production and release of tritium. The FHR community is currently investigating various techniques to solve this tritium management challenge. One of the methods investigated is inert gas sparging which has been investigated during the Molten Salt Reactor Experiment (MSRE) in the 1960’s and 1970’s. To enhance the efficiency of this technique, high power ultrasonics can ...


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